Parametric optimizartion of microdrilling in aerospace material

Abstract

Drilling is one of the basic machining process of making holes and it is essentially for manufacturing industry like Aerospace industry, watch manufacturing industry, Automobile industry, medical industries and semiconductors.. In this study, An attempt has been taken to minimize the thrust forces, Circularity Error and Burr size reduction in the micro drilling process on a PMMA (Poly methyl methacrylate) strip of 95*30*4mm by application of the DOE (Design of Experiment) method integrated with Grey Relational Analysis. Taking into account the drilling thrust, Circularity and burr size, 2 machining Controllable parameters such as federate, spindle speed, are optimized based on the DOE method. A Run order was developed by taking the two factors each having 3 levels using Statistical package. Based on the sequence, drilling was done by taking HSS drill bit of size 1mm dia. The resultant data are analysed by Grey relational analysis to find out a combination of optimal drilling conditions. In particular, it is found that high speed and low feed is giving a better result having low circularity error and small burr size.